Re: Formatting Objects considered harmful

Subject: Re: Formatting Objects considered harmful
From: Paul Prescod <paul@xxxxxxxxxxx>
Date: Mon, 19 Apr 1999 12:07:04 -0500
Håkon Wium Lie wrote:
> 
> Alas, many people consider HTML to be a formatting language and use it
> accordingly. This is wrong and W3C tries to educate people otherwise.
> Deprecating a bunch of presentational tags in HTML 4 is a clear sign
> of direction.

Yes and no. As long as HTML has inline STYLE attributes you will still be
able to use it as a presentational language without much effort.

> Unless the semantics of the vocabulary is known on the other side, the
> client is worse off receiving arbitrary XML than receiving documents
> that have been downtranslated (as in the ladder of abstraction) to
> HTML or XHTML. I don't see any significant bandwidth or performance
> issues here.

It depends on what you man by "semantics" and "known". I can send a
DocBook document and an XSL->HTML mapping across and that is more useful
than sending just the HTML output. The important point is that we don't
have to *agree* on the semantics in advance. We just have to agree on an
extension mechanism (stylesheet, Java applet, JavaScript+DOM code, etc.)
That's why I disagree with this quote:

> > Publishing semantically rich XML should be encouraged when the 
> > semantics is globally known, e.g. MathML. Publishing arbitrary
> > XML should be discouraged. 

I would say: "publishing semanticaly rich XML should be encouraged only
when there is also an accessible, well-defined mapping to the globally
known language with the richest semantics." For some applications that
will be MathML, for others it will be HTML, for others, only SVG.

> This is an interesting idea. But, given that you are so close to HTML,
> why not use HTML (or, more likely XHTML) with a few CLASS attributes?

Why not use CLASS attributes? Because now you are asking us to completely
change the XSL processing model -- and make it more complex. You are
saying that XML users should always define a mapping from XML->HTML and
then another mapping from HTML+CLASS into the CSS formatting model. In
some (but not all) situations you will have doubled the complexity and
gained nothing.

Yes, converting to HTML+CLASS makes sense in some circumstances. But
converting to an inline-style friendly language makes sense in other
circumstances. I think that the inline-style language could be based on
HTML instead of FOs. But we would have to make inline style in "HTMLSTYLE"
much more convenient. As I've argued with Chris Lilley, the "STYLE"
attribute does not cut it.

I'm all for using "HTMLSTYLE" instead of formatting objects but we need to
be willing to make the extensions to HTML required to make it easy to
generate as an inline-style language. I don't think we are.

-- 
 Paul Prescod  - ISOGEN Consulting Engineer speaking for only himself
 http://itrc.uwaterloo.ca/~papresco

"The Excursion [Sport Utility Vehicle] is so large that it will come
equipped with adjustable pedals to fit smaller drivers and sensor 
devices that warn the driver when he or she is about to back into a
Toyota or some other object." -- Dallas Morning News


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